AGRICULTURAL FORMULATION COMPRISING AN AGRICULTURAL ACTIVE AND A PHOSPHATED ALCANOL AS ADJUVANT

Abstract

The present invention relates to the use of phosphated 2-propylheptanol, phosphated 2- proyplheptanol alkoxylate and/or mixtures thereof in agricultural formulations. The invention also relates to agricultural formulations comprising the aforementioned adjuvants, and to methods of treating a plant with the agricultural formulations of the invention.

Full Text

Field of Invention
The present invention relates to the use of phosphated 2- propylheptanol or a phosphatcd
2-propylheptanol alkoxylate as an adjuvant in agricultural formulations. More
specifically, it relates to the use of phosphated
hydroxyl compounds as a dispersant, emulsifier, hydrotrope, wetting agent,
compatability agent and the like in agricultural formulations.
Background of the Invention
The agricultural chemical formulator has the difficult task of creating
a product that balances bioefficacy, toxicity, cost, shelf life and user friendliness.
Of particular importance to the activity of an agricultural formulation is the ability of an
aqueous solution to spread evenly over a surface, the so-called wetting
ability, and the effective uptake of the active ingredient by the plant to be
treated. For example, in agricultural formulations, efficacy benefits from a good
wetting of the plant surface and uptake of the active ingredient.
Adjuvants arc added to agricultural formulations to improve activity,
thereby reducing the amounts of active ingredients necessary, resulting in lower
application cost. They generally take the form of surface-active or salt-like
compounds and depending on their mode of action, they are classified as
modifiers, activators, fertilizers and/or pH buffers.
Surfactants are generally regarded as modifiers and/or activators as
they improve wetting properties and uptake of the active ingredients in the
agricultural formulation. Additionally, some surfactants improve the solubility of
active ingredients in formulations thereby eliminating serious issues such as
product separation and/or crystallization.
Anionic, cationic, amphoteric and nonionic surfactants are all known
and used in agricultural applications depending on the desired effect. For

example, nonionic surfactants are known to be good wetting agents, and are
often present in agricultural formulations. Many nonionic surfactants are not
soluble enough in solutions with a high amour t of electrolytes, such as alkali
and/or alkaline complexing agents, salts, and the like and therefore need the
presence of a hydrotrope to improve the solubility. A number of hydrotropes for
nonionic surfactants have been described in various publications. Examples of
such hydrotropes are ethanol, sodium xylene sulphonate, sodium cumene
sulphonate, alkyl glycosides, and phosphated alkoxylated alcohols.
However, there is still a need for new efficient surfactants that can
improve activity, act as effective hydrotropes, and are compatible for the
achievement of stable formulations delivering optimal performance. The
objective of the present invention is, therefore, to find a new hydrotrope that is
efficient in formulating agricultural compositions, which compositions will remain
homogeneous upon dilution, and where the performance of the compositions is
good.
Accordingly, it is an object of the present invention to provide an
improved agricultural adjuvant. It is also an object of the invention to provide a
stable, agricultural formulation having improved activity. These and other
objects are achieved by the adjuvants/formulations of the present invention.
Summary of the Invention
The present invention relates to the use of phosphated 2-
propylheptanol, phosphated 2-propylheptanol alkoxylate and/or mixtures thereof
as agricultural adjuvants. The invention also relates to agricultural formulations
comprising same, and to methods of treating a plant with the agricultural
formulations of the invention.

Detailed Description of the Invention

The invention relates to the use of phosphated 2-propylheptanol or
phosphated 2-propylheptanol alkoxyiates as a hydrotrope in agricultural

formulations. More specifically, it relates to an agricultural adjuvant that
comprises at least one phosphated hydroxyl compound. The adjuvant of the
invention can effectively be utilized as a dispersant, emulsifier, hydrotrope,
wetting agent, compatability agent and /or the like in agricultural formulations.
In this regard, the inventors have found that phosphated 2-propylheptanol or a
phosphated 2-propylheptanol alkoxylate where the alkoxylate on the average
comprises 1-20, preferably 1-15, more preferably 2-10, and most preferably 2-6
ethyleneoxy units and 0-3, preferably 0-2 propyleneoxy and/or butyleneoxy
units, is an efficient hydrotrope and activity improver in agricultural formulations.
The adjuvants of the invention improve wetting and uptake of active ingredients
by a plant, resulting in a higher activity at a given application rate.
In another embodiment, the invention relates to aqueous agricultural
formulations comprising at least one agricultural active, and 0.1-30, preferably
0.1-20, and most preferably 0.1-10% by weight of the adjuvant of the present
invention.
The adjuvants of the invention can be used with any active ingredient
in order to improve efficacy by improving the dispersion or emulsions properties
in the application tank, or modifying the spreading and/or penetration properties
of the spray solution on the plant. Examples of active ingredients include, but
are not limited to herbicides, fungicides, insecticides, plant growth regulators
and the like.
The following is a non-limiting list of active ingredients that can be employed:
Herbicides (examples, but not limited to):
• amide herbicides
allidochlor
beflubutamid
benzadox
benzipram
bromobutide
cafenstrole
CDEA
cyprazole

where M is H, a monoyalent metal ion or R1R2R3R4N+, where R1, R2, R3, and R4
are H, an alkyl group with 1-4 carbon atoms or -CH2CH2OH, and c is a number
1-20, preferably 2-10, more preferably 2-6, eyen more preferably 2-4, and most
preferably 3.
Phosphated 2-propylheptanol or a phosphated 2-propylheptanol
alkoxylate may be obtained by different processes, the most common being the
reaction of 2-propylheptanol or alkoxylated 2-propylheptanol with
polyphosphoric acid or phosphorous pentoxide (P2O5).
In the process using polyphosphoric acid the resulting product
mixture wit! predominantly contain the monoalkylphosphate ester of 2-
propylheptanol or of alkoxylated 2-propylheptanol and only a small amount
(
phosphate residues from the polyphosphoric acid, such as orthophosphoric
acid, will be present.
When P2O5 is used as the phosphatising reagent and the molar ratio
between P205 and alcohol or alkoxylated alcohol is 1:3, the product mixture will
contain about equal amounts of monoalkylphosphate ester and
dialkylphosphate ester, and only smaller amounts of inorganic phosphate
residues. A larger amount of alcohol or alkoxylated alcohol will yield more
diester, and a smaller amount will yield more monoester. It will be known to a
person skilled in the art how to synthesise phosphate esters with certain
amounts of mono- and dialkyl phosphate esters. For a general description of
phosphate esters see, e.g., Anionic Surfactants Vol. 7, Part ll, pages 504-511 in
Surfactant Science Series, edited by Warner M. Linfield, Marcel Dekker Inc.,
New York and Basle 1976. The alcohol alkoxylates to be phosphated may be
either of the standard type produced by using an alkaline catalyst such as KOH,
or of the narrow range type produced by using a narrow range catalyst, such as
an acid catalyst, Ca(OH)2 or hydrotalcite.

if necessary, the reaction mixture resulting from either of the
procedures can be neutralized by an organic or inorganic base before use. The
base may be, e.g., an alkali hydroxide, such as sodium hydroxide or potassium
hydroxide; ammonia, an alkanolamine, such as monoethanolamine,
triethanolamine or methyldiethanolamine; or an alkylamine such as
triethylamine.
The monoalkylphosphate ester of 2-propylheptanol or of ethoxylated
2-propylheptanol has the formula

where M is H, a monoyalent metal ion or R1R2R3R4N+, where R1 R2, R3, and R4
are H, an alkyl group with 1-4 carbon atoms or -CH2CH2OH, and c is a number
0-20, preferably 2-10, more preferably 2-6, eyen more preferably 2-4, and most
preferably 3. The product mixture resulting from the reaction of 2-propylheptanol
or of ethoxylated 2-propylheptanol with polyphosphoric acid may also contain
smaller amounts of products containing more than one phosphate unit
according to the formula

where n is 1-3 and M and c haye the same meaning as aboye.
For ethoxylates containing smaller amounts of ethyleneoxy units,
also a certain amount of unethoxylated product will remain due to the
distribution of ethyleneoxy units. This unethoxylated product will also be
phosphatised during the reaction with the phosphatising agent, and thus the
phosphate ester of 2-propylheptanol will also be present in the reaction mixture
resulting from these aboye-mentioned ethoxylates.
The dialkylphosphate ester of 2-propylheptanol has the formula

where M and c haye the same meaning as aboye. The product mixture resulting
from the reaction of 2-propylheptanol or ethoxylated 2-propylheptanol with P205
may also contain a dialkyl diphosphate ester according to the formula

where M and c haye the same meaning as aboye. This type of diester may be
hydrolysed to yield 2 moles of monoester.
2-Propylheptanol is normally made by a process resulting in small
amounts of by-products such as 4-methyl-2-propylhexanol and 5-methyl-2-
propylhexanol. These products or their ethoxylates will also be phosphated
during the process, and the phosphated species will be comprised in the
resulting product mixture.
The reaction mixtures obtained by the phosphatising procedures are
normally used as such without any purification procedure, but both the mixtures
and the purified phosphate esters function as hydrotropes. To act as a good
hydrotrope, the mixture should predominantly contain the monoalkyl phosphate
esters, since these are better hydrotropes than the dialkyl phosphate esters.
Preferably more than 60, more preferably more than 70, and most preferably
more than 80% by weight of the mixture should be monoalkyl phosphate esters.
The phosphated 2-propylheptanol or phosphated 2-propylheptanol
alkoxylates where the alkoxyfate on ayerage comprises 1-20, preferably 2-10,
more preferably 2-6, eyen more preferably 2-4, and most preferably 3,
ethyleneoxy units and 0-3, preferably 0-2, propyleneoxy and/or butyleneoxy,

preferably propyleneoxy, units described aboye and a process for their
production are already partly disclosed in the earlier mentioned publications EP-
A-256427 and CH-A-481953 for use as dispersants for pigments and as
additiyes in an emulsion polymerisation process, respectiyely. Howeyer, the
phosphated 2-propylheptanol alkoxylate where the alkoxylate comprises 2-4,
preferably 3, ethyleneoxy units on ayerage is especially efficient as a
hydrotrope compared to the other phosphated alkoxylates of 2-propylheptanol
(see Table 1 in the Examples). Therefore, the inyention also relates to the
phosphated 2-propylheptanol alkoxylate where the alkoxylate on ayerage
comprises 2-4, preferably 3, ethyleneoxy units per se and a process for its
production.
The agricultural formulations of the inyention may contain alkali,
preferably sodium or potassium hydroxide, and ah alkaline complexing agent
that may be inorganic as well as organic. Typical examples of inorganic
complexing agents used in the alkaline composition are alkali salts of silicates
and phosphates such as sodium silicate, sodium metasiiicate, sodium
tripolyphosphate, sodium orthophosphate, sodium pyrophosphate, and the
corresponding potassium salts. Typical examples of organic complexing agents
are alkaline aminopolyphosphonates, organic phosphates, polycarboxylates,
such as citrates; aminocarboxylates, such as sodium nitriiotriacetate (Na3NTA),
sodium ethylenediaminetetraacetate (EDTA), sodium
diethylenetriaminepentaacetate, sodium 1,3-propylenediaminetetraacetate, and
sodium hydroxyethylethylenediaminetriacetate. The amount of alkali present in
the composition depends on the application and on whether the composition is
a concentrate or a ready-to-use solution.
The concentrated compositions of the present inyention are stable
and in many cases generally clear. The clarity interyal is suitably between 0-
40°C, preferably between 0-50°C, and most preferably between 0-60°C. This
may be adapted by changing the ratio of hydrotrope to nonionic surfactant. The

concentrate normally contains 50-95% by weight of water, suitably 70-90% by
weight.
To obtain a ready-to-use solution the concentrates are diluted with
water and/or fertilizer solutions up to 1:40. The diluted solutions are also clear
and stable, but in some cases they may turn a little bit hazy although they are
still stable and do not separate. The ready-to-use solutions exhibit good
properties. A typical concentrate formulation contains 3-5% by weight of the
adjuyant according to the present inyention, while a ready-to-use formulation
would normally contain 0.2-1% by weight of same.
Tank mixes can include multiple pesticides mixed together, targeting
multiple pests, while using water as the deliyery medium. In that case the
adjuyant would help preyent incompatibilities that could occur when mixing
different formulation types together, such as emulsifiable concentrates and
suspension concentrates.
Tank mixes can also include pesticide(s) dispersed or emulsified in a
fertilizer solution. The adjuyants of the present inyention function to facilitate
the dispersion or emulsification of the pesticides(s) in the salt solutions by
coupling the surfactants into the electrolyte solution.
The present inyention is further illustrated by the following Examples.
Example 1
This example relates to a comparison between phosphated 2-propylheptanol +
5 EO and phosphated hexanol + 5 EO as hydrotropes for 2-propylheptanol + 5
EO.

A smaller amount of phosphated 2-propy!heptanol+5EO, as compared to
phosphated hexanol+5EO, was required to obtain a clarity interyal of 0-60°C.
The formulations with phosphated 2-propylheptanol + 5 EO as a hydrotrope
were also much more stable upon dilution.
Example 2
This example compares a number of phosphated ethoxylated alcohols with
phosphated 2-propylheptanol + 5 EO as a hydrotrope for 2-propylheptanol + 5
EO.

The formulation according to the inyention exhibited the best cleaning
performance of all the inyestigated formulations, in combination with a good
stability upon dilution.
Example 3
In this example the wetting ability of a composition according to the inyention
was measured by the modified Draye's test.

In the modified Draye's test, the sinking time in s is measured for a specified
cotton yarn in approximately 0.1 % surfactant solution. The formulation in the
Table 5 was diluted with distilled water to 0.1 % by weight with respect to the Cg-
C11-alcohol + 4 EO, and the modified Draye's test was performed on this
solution. The result is displayed in the Table 6, below.

The formulation containing the phosphated 2-propylheptanol + 5 EO as a
hydrotrope for the ethoxylate had a good wetting ability, whereas for the
different components alone, the wetting time was >420 s. The Cg-C11-alcohol is
not soluble in this alkaline medium without a hydrotrope, and the phosphated 2-
propylheptanol + 5 EO has no good wetting ability on its own. When the
hydrotrope is added, the nonionic surfactant is solubilised, and it is then able to
exert its wetting ability.

Example 4
In the syntheses described below a 1,000 cm3 flange flask equipped with an
anchor stirrer was used. The reactor was heated by an electrical heater
equipped with a thermostat. A slight flow of nitrogen was applied during the
reaction. The polyphosphoric acid (PPA) used was Polyphosphoric acid 116,
84% equiyalent in P2Os (Albright & Wilson).
1) 2-propylheptanoi + PPA
2-propylheptanol (222.47 g, 1.41 mole) was charged and heated to 45°C. PPA
(254.09 g) was added from a 60 ml syringe and the exothermic reaction was
kept at 55-70°C while stirring at 240 r/min. PPA was added during a period of 1
hour. The reaction was then left for 2 h at 60°C and with stirring at 300 r/min.
After the post-reaction water (5.0 g) was added to hydrolyse the remaining PPA,
after which the acid was neutralised with KOH (274.4 g) dissolyed in 555.0 g
water.
2) 2-propylheptanol + 3 EO +PPA
2-propylheptanol +3 EO (295.63 g, 1.02 mole) was charged and heated to
45°C. PPA (184.95 g) was added from a 60 ml syringe and the exothermic
reaction was kept at 55-70°C while stirring at 240 r/min. PPA was added during
a period of 1 hour. The reaction was then left for 2 h at 60°C and with stirring at
300 r/min. After the post-reaction water (5.0 g) was added to hydrolyse the
remaining PPA, after which the acid was neutralised with KOH (191 g)
dissolyed in 454 g water.
3) 2-propylheptanol + 5 EO + PPA
2-propylheptanol + 5 EO (307.71 g, 0.81 mole) was charged and heated to
45°C. PPA (148 g) was added from a 60 ml syringe and the exothermic reaction
was kept at 55-70°C while stirring at 240 r/min. PPA was added during a period
of 1 hour. The reaction was then left for 2 h at 600C and with stirring at 300
r/min. After the post reaction water (5.0 g) was added to hydrolyse the
remaining PPA, after which 374.02 g acid were neutralised with KOH (132.37 g)
dissolyed in 517 g water.

Example 5
Morwet D-425 is a condensed alkyl naphthalene sulfonate dispersant
commercially ayailable from Akzo Nobel Surface Chemistry LLC, Chicago, IL,
that has been used as the main dispersant in yarious pesticide suspension
concentrate, wettable powder and water dispersible granule formulations.
Frequently, a nonionic surfactant is used as a co surfactant to increase the
wetting and stability of the formulations. Since the solubility of nonionic
surfactants is decreased in the salt solution, flocculation will occur when
pesticide formulation is mixed with fertilizer during application. This example is
aimed to compare the performance of different co surfactant in Atrazine SC and
to yerify if the branched hydrophobe improyes the compatibility in ammonium
nitrate solution.
Materials
Atrazine Tech.
Morwet D-425 (condensed alkyl naphthalene sulfonate, sodium salt)
Ethylan 1005 phosphate ester (2-propyl heptanol + 5EO)
Emphos PS -131 (iso-tridecanol + 6EO, phosphate ester, acid form)
Emphos PS-236 (linear C10/12 alcohol + 5EO, phosphate ester, acid form)
Witconol SN-70 (linear C10/12 alcohol + 5EO)
Witconol TD-60 (iso-tridecanol + 6EO)
Ethylan 1005 (2-propy! heptanol + 5EO)
Urea - ammonium nitrate
The Atrazine suspensions were made by first dissolying the Morwet D-425 and
wetting agent in the appropriate yolume of water. Micronized Atrazine technical
was then added to the solution and then dispersed using high shear. All of the
suspensions tested were made to contain 480 grams per liter of actiye
ingredient.

After preparing the Atrazine suspensions with different surfactant systems, the
suspensions were diluted into UAN and eyaluated based on the degree of
flocculation as a function of time.
Formulations/Results/Obseryations

Next, 5 mL of each sample were poured in 95 mL of UAN solutions in 100 ml_
tubes. The tubes were inyerted 10 times and obseryed for floccuiation. After
sitting for 1, 2, 4, and 24 hours, the height of clear UAN solution from the bottom
of tube was measured. The following results were found:

As seen aboye, all the co surfactants decreased the SC compatibility in UAN solution
because the salt precipitated the co surfactant from the system. Howeyer, Efhylan 1005
phosphate ester (contained in sample 1996-17-1) did perform much better compared to
other cosurfactants in the relatiyely short time period (up to 4 hr).
The difference in the results among formulations was significant enough to indicate that
different hydrophobe lengths and branches can play an important role for compatibility
issue.

Based on the data generated in this study, Ethylan 1005 phosphate ester showed the
potential to improye the SC compatibility with UAN solution.

We Claim: '
1. An agricultural formulation comprising at least one agricultural actiye, and at least one
agricultural adjuyant, wherein said adjuyant comprises at least one phosphated 2-
propylheptanol, phosphated 2-propylheptanol alkoxylate, or mixtures thereof, and wherein
said agricultural actiye is a herbicide, fungicide, insecticide, plant growth regulator, or
mixtures thereof.
2. The formulation as claimed in claim 1 wherein the alkoxylate on ayerage comprises 1 to 20
ethyleneoxy units and 0-3 propyleneoxy and/or butyleneoxy units.
3. The formulation as claimed in claim 1 wherein the phosphated 2-propylheptanol or the
phosphated 2-propylheptanol alkoxylate has the formula

where M is H, a monoyalent metal ion or R1R2R3R4N+, where R1, R2, R3, and R4 are H, an
alkyl group with 1-4 carbon atoms or -CH2CH2OH, and c is a number 0-20.
4.The formulation as claimed in claim 2 wherein the adjuyant comprises a mixture
containing two or more of

wherein n is 1-3 and M and c haye the same meaning as in claim 3,
compounds of the formula
- compounds of formula II,
- compounds of the formula

wherein M and c haye the same meaning as in claim 3, and
compounds of the formula

wherein M and c haye the same meaning as in claim 3,
and where II is present in an amount of at least 60% by weight of the adjuyant mixture.
5. The formulation as claimed in claim 1 wherein said phosphated 2-propylheptanol
alkoxylate comprises 2 to 4 ethyleneoxy units.
6.The formulation as claimed in claim 5 wherein the phosphated alkoxylate comprises one or
more products of the formulae

wherein M is H, a monoyalent metal ion or R1R2R3R4N+, where R1, R2, R3, and R4 are H,
an alkyl group with 1-4 carbon atoms or -CH2CH2OH, and c is a number 2-4,

wherein n is 1-3, M is H, a monoyalent metal ion or R1R2R3R4N , where R1, R2, R3, and R4
are H, an alkyl group with 1-4 carbon atoms or -CH2CH2OH, and c is a number 0-20,

wherein M and c haye the same meaning as aboye, and

wherein M and c haye the same meaning as aboye.
7.The agricultural formulation as claimed in claim 1 which comprises 0.1-30% by weight of
said adjuyant that comprises phosphated 2-propylheptanol and/or a phosphated 2-
propylheptanol alkoxylate, where the alkoxylate on ayerage comprises 1 to 20 ethyleneoxy
units and 0-3 propyleneoxy units.
8.The formulation as claimed in claim 7, wherein said adjuyant is a phosphated 2-
propylheptanol alkoxylate comprising 2-4 ethyleneoxy units.
9.The formulation as claimed in claim 6 wherein in said one or more phosphated 2-
propylheptanol alkoxylates haying the formulae II, III, IV and/or V, the phosphated 2-
propylheptanol alkoxylates haying the formulae II is present in an amount of at least 80%
by weight of the adjuyant mixture.
10.The formulation as claimed in claim 1 wherein said adjuyant acts as a dispersant,
emulsifier, hydrotrope, wetting agent, and/or compatability agent.

The present invention relates to the use of phosphated 2-propylheptanol, phosphated 2-
proyplheptanol alkoxylate and/or mixtures thereof in agricultural formulations. The
invention also relates to agricultural formulations comprising the aforementioned
adjuvants, and to methods of treating a plant with the agricultural formulations of the
invention.